1. Field of the Invention
This invention relates to tooth whitening compositions, and, more particularly, to a liquid, substantially anhydrous tooth whitening composition for effective delivery of a tooth whitening ingredient onto teeth, which exhibits excellent bioadhesion and retention thereon, advantageous penetration through tooth enamel, superior bleaching of stained teeth, and a predetermined Brookfield viscosity which provides for multiple methods of delivery of the tooth whitening ingredient onto teeth.
2. Description of the Prior Art
Since the early 1980s, the tooth whitening industry has grown from a scenario in which one could only receive tooth whitening treatments in a dental office to the scenario that exists today in which numerous competitors sell over-the-counter tooth whitening systems including delivery systems such that the average consumer can whiten their teeth in their own home without medical supervision.
Numerous delivery systems have become popular and well known including those employing strips coated with the tooth whitening substance, trays filled with tooth whitener, tooth whiteners incorporated into toothpaste, and other paint-on applicators such as those analogous to felt tip pens, and others using brushes with bristles and foam-type brush applicators. Over-the-counter whiteners today fall into three categories—trays and gels, strips and paint-on whiteners.
Tray and gel systems are designed for the user to fill the flexible tray with the whitening formulation and this is placed on the teeth. The gel extrudes out of the tray on the gingival and the mucosa with a great chance of soft tissue irritation. Strips are placed on the teeth with a good portion of the strip laying on the gingival area and also causing irritation.
A successful tooth whitening composition requires that the following parameters be favorable:
(1) A sufficient amount of activated active ingredient, e.g. H2O2 present in and delivered by the composition;
(2) an enhanced degree of retention of the composition onto teeth; i.e. its bioadhesion, which is determined by the ratio of its cohesive energy to surface energy;
(3) a favorable degree of penetration of the composition into the tooth enamel;
(4) a suitable viscosity to deliver the composition by selected desirable means; and,
(5) efficacy of bleaching of stained teeth enamel by the composition.
Accordingly, it is the object of this invention to provide a tooth whitener composition having, in combination:
(1) a predetermined concentration of active H2O2 in a film-forming complex; which provides for;
(2) effective bioadhesion/retention of the composition on teeth;
(3) advantageous penetration of the composition into the tooth enamel;
(4) a predeterminable viscosity to deliver the composition onto teeth by one or more suitable delivery means; and
(5) excellent bleaching action on stained teeth.
The following patents illustrate suitable active tooth whitening substances and delivery systems therefor: U.S. Pat. Nos. 5,077,047, U.S. Pat. No. 5,108,742; U.S. Pat. No. 5,122,370; U.S. Pat. No. 5,130,124; U.S. Pat. No. 5,183,901; U.S. Pat. No. 5,190,749; U.S. Pat. No. 5,206,385; U.S. Pat. No. 5,312,619; U.S. Pat. No. 5,989,569; U.S. Pat. No. 6,669,930; U.S. Pat. No. 6,770,266; U.S. Pat. No. 6,893,629 and U.S. 2003/0203338A1.
These and other objects and features of the invention will be made apparent from the following description.